Onesies are a good idea, and print out papers to tape EVERYWHERE. On your wall, on the bassinet.
When we were in the NICU, I was confident that the nurses knew how to care for him properly. They were fairly anti circumcision, wouldn't do it in the hospital, etc.
However when my child was in the PICU, he was catheterized while my husband was "on duty"... but he was asleep and DS was retracted completely. I was unconsolable. Just a few days before I had let him down by allowing them to cath him for a sample- they didn't tell me it was for a sample they acted like he needed a foley put in. So over a period of a week, he was retracted twice.
So I put signs up everywhere stating if ANY handling of his penis was necessary, that I needed to be there. Not my husband, not his regular nurse, ME. The doctor made a snide remark that "Everyone knows not to retract a foreskin" but the fact of the matter was that he HAD been retracted and it wasn't going to happen again.. I was steaming.
and, he was wrong. When we moved to the pediatric floor TWO nurses asked me why you shouldn't retract a foreskin. Luckily one was pregnant with a boy and open to hearing what I had to say..
... I know its a different situation but the signs did the trick. When he was in an isolette I hung it so it would smack them in the face if they leaned over to look at him.
after these incidents, I also wrote EVERYTHING in permanent marker on the front of his med book. Cloth diapers, treated for thrush, do not retract, no artificial nipples without mom's specific consent, blah blah blah all of it. I figured the cost of replacing the binder would be less than the lawsuit they would be smacked with if they disobeyed it.